La investigación en la Universidad

[Actas de:] "La Universidad española a examen: Jornadas sobre la Investigación en la Universidad" (25 y 26 de febrero de 1999: Universidad Carlos III de Madrid)Con motivo del X aniversario de la Universidad Carlos III de Madrid, el Instituto Antonio de Nebrija de Estudios sobre la Universidad organizó durante los días 25 y 26 de febrero de 1999 un encuentro titulado La universidad española a examen: Jornadas sobre investigación en la Universidad. En el encuentro celebrado participaron representantes de distintos ámbitos científicos, con el fin de ofrecer una visión más completa del panorama actual de la investigación en la Universidad, dejando constancia de las opiniones de la empresa, las universidades, las instituciones políticas, los organismos públicos de investigación. Este libro recoge sus resultados.Prólogo / Carmen Merino. -- Programa. -- Presentación / Gregorio Peces-Barba. -- La Investigación en la Universidad. Una opinion / César Nombela. -- Los Institutos Universitarios como estructuras organizativas de la investigación / José Manuel González Ros. -- Valoración de la investigación en la universidad española / Pedro Ramos Castellanos. -- Universidad e investigación. Por la diversidad y la rebeldía / Juan Urrutia. -- La universidad española, una fuente de tecnología necesaria para la empresa / Juan Mulet Meliá. -- Relaciones universidad y empresa. Una aportación empresarial / Ángel Martínez Román. -- Algunas reflexiones sobre el III Plan Regional de Investigación Científica e Innovación Tecnológica / Enrique Otero. -- Centros de Apoyo a la Investigación (CAI) / Juan Carlos Prieto Villapún. -- Infraestructuras científicas necesarias en la Comunidad de Madrid / Rodolfo Miranda. -- Importancia de los recursos humanos en relación con la I+D en Universidades / José Luis Sotelo. -- Investigación y Universidad / Alfonso Ruiz Miguel. -- Sobre el actual sistema de financiación de I+D / José Ramón Casar Corredera. -- Universidad e investigación: Hacia unas nuevas referencias en el contexto del Sistema Ciencia-Tecnología-Sociedad / Francisco Marcellán. -- Políticas de I+D en la Comunidad de Madrid / Francisco Rubia Vila. -- Perspectivas del Nuevo Plan Nacional de I+D / Javier Pascual Casado. -- Primer debate. Moderador Enrique Villalba. -- Segundo debate. Moderadora Adela Mora. -- Tercer debate. Moderador Francisco Marcellán. -- Clausura / Francisco Marcellán. -- Epílogo / Clara Eugenia Garcí

Brain imaging of the cortex in ADHD: a coordinated analysis of large-scale clinical and population-based samples

Objective: Neuroimaging studies show structural alterations of various brain regions in children and adults with attention deficit hyperactivity disorder (ADHD), although nonreplications are frequent. The authors sought to identify cortical characteristics related to ADHD using large-scale studies. Methods: Cortical thickness and surface area (based on the Desikan–Killiany atlas) were compared between case subjects with ADHD (N=2,246) and control subjects (N=1,934) for children, adolescents, and adults separately in ENIGMA-ADHD, a consortium of 36 centers. To assess familial effects on cortical measures, case subjects, unaffected siblings, and control subjects in the NeuroIMAGE study (N=506) were compared. Associations of the attention scale from the Child Behavior Checklist with cortical measures were determined in a pediatric population sample (Generation-R, N=2,707). Results: In the ENIGMA-ADHD sample, lower surface area values were found in children with ADHD, mainly in frontal, cingulate, and temporal regions; the largest significant effect was for total surface area (Cohen’s d=−0.21). Fusiform gyrus and temporal pole cortical thickness was also lower in children with ADHD. Neither surface area nor thickness differences were found in the adolescent or adult groups. Familial effects were seen for surface area in several regions. In an overlapping set of regions, surface area, but not thickness, was associated with attention problems in the Generation-R sample. Conclusions: Subtle differences in cortical surface area are widespread in children but not adolescents and adults with ADHD, confirming involvement of the frontal cortex and highlighting regions deserving further attention. Notably, the alterations behave like endophenotypes in families and are linked to ADHD symptoms in the population, extending evidence that ADHD behaves as a continuous trait in the population. Future longitudinal studies should clarify individual lifespan trajectories that lead to nonsignificant findings in adolescent and adult groups despite the presence of an ADHD diagnosis

Analysis of structural brain asymmetries in attention-deficit/hyperactivity disorder in 39 datasets

Objective Some studies have suggested alterations of structural brain asymmetry in attention-deficit/hyperactivity disorder (ADHD), but findings have been contradictory and based on small samples. Here, we performed the largest ever analysis of brain left-right asymmetry in ADHD, using 39 datasets of the ENIGMA consortium. Methods We analyzed asymmetry of subcortical and cerebral cortical structures in up to 1,933 people with ADHD and 1,829 unaffected controls. Asymmetry Indexes (AIs) were calculated per participant for each bilaterally paired measure, and linear mixed effects modeling was applied separately in children, adolescents, adults, and the total sample, to test exhaustively for potential associations of ADHD with structural brain asymmetries. Results There was no evidence for altered caudate nucleus asymmetry in ADHD, in contrast to prior literature. In children, there was less rightward asymmetry of the total hemispheric surface area compared to controls (t = 2.1, p = .04). Lower rightward asymmetry of medial orbitofrontal cortex surface area in ADHD (t = 2.7, p = .01) was similar to a recent finding for autism spectrum disorder. There were also some differences in cortical thickness asymmetry across age groups. In adults with ADHD, globus pallidus asymmetry was altered compared to those without ADHD. However, all effects were small (Cohen’s d from −0.18 to 0.18) and would not survive study-wide correction for multiple testing. Conclusion Prior studies of altered structural brain asymmetry in ADHD were likely underpowered to detect the small effects reported here. Altered structural asymmetry is unlikely to provide a useful biomarker for ADHD, but may provide neurobiological insights into the trait

Subcortical brain volume, regional cortical thickness, and cortical surface area across disorders: findings from the ENIGMA ADHD, ASD, and OCD Working Groups

Objective Attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and obsessive-compulsive disorder (OCD) are common neurodevelopmental disorders that frequently co-occur. We aimed to directly compare all three disorders. The ENIGMA consortium is ideally positioned to investigate structural brain alterations across these disorders. Methods Structural T1-weighted whole-brain MRI of controls (n=5,827) and patients with ADHD (n=2,271), ASD (n=1,777), and OCD (n=2,323) from 151 cohorts worldwide were analyzed using standardized processing protocols. We examined subcortical volume, cortical thickness and surface area differences within a mega-analytical framework, pooling measures extracted from each cohort. Analyses were performed separately for children, adolescents, and adults using linear mixed-effects models adjusting for age, sex and site (and ICV for subcortical and surface area measures). Results We found no shared alterations among all three disorders, while shared alterations between any two disorders did not survive multiple comparisons correction. Children with ADHD compared to those with OCD had smaller hippocampal volumes, possibly influenced by IQ. Children and adolescents with ADHD also had smaller ICV than controls and those with OCD or ASD. Adults with ASD showed thicker frontal cortices compared to adult controls and other clinical groups. No OCD-specific alterations across different age-groups and surface area alterations among all disorders in childhood and adulthood were observed. Conclusion Our findings suggest robust but subtle alterations across different age-groups among ADHD, ASD, and OCD. ADHD-specific ICV and hippocampal alterations in children and adolescents, and ASD-specific cortical thickness alterations in the frontal cortex in adults support previous work emphasizing neurodevelopmental alterations in these disorders

Neurofisiología de la memoria operativa viso-espacial

El gran auge que ha experimentado en los últimos años el estudio de la memoria operativa, hace necesaria la recopilación de los hallazgos más relevantes de su funcionamiento y fisiología. En concreto, los estudios que a continuación se presentan tratan de determinar la naturaleza del componente viso-espacial de la memoria operativa. Para ello, se han recopilado investigaciones realizadas tanto en primates como en humanos. Éstas también incluyen estudios con muestra clínica. De este conjunto de investigaciones se desprende que hay una red de áreas corticales implicadas en la retención de un estímulo viso-espacial (p. ej. corteza prefrontal, áreas parietotemporales y occipitotemporales): y que estas regiones están muy próximas o posiblemente son las mismas que aquellas que codifican las características sensoriales de los estímulos. Es importante mantener una sintonía entre el laboratorio y la clínica diaria, que en último término va a ser la beneficiaria de los nuevos hallazgos sobre memoria viso-espacia

Psicothema

Resumen en inglés y castellanoEl gran auge que ha experimentado en los últimos años el estudio de la memoria operativa, hace necesaria la recopilación de los hallazgos más relevantes de su funcionamiento y fisiología. En concreto, los estudios que se presentan tratan de determinar la naturaleza del componente viso-espacial de la memoria operativa. Para ello, se han recopilado investigaciones realizadas tanto en primates como en humanos. Éstas también incluyen estudios con muestra clínica. De este conjunto de investigaciones se desprende que haya una red de áreas corticales implicadas en la retención de un estímulo viso-espacial (p.ej. corteza prefrontal, áreas parietotemporales y occipitotemporales); y que estas regiones están muy próximas o posiblemente son las mismas que aquellas que codifican las características sensoriales de los estímulos. Es importante mantener una sintonía entre el laboratorio y la clínica diaria, que en último término va a ser beneficiaria de los nuevos hallazgos sobre memoria viso-espacial..AsturiasES

Evidence for similar structural brain anomalies in youth and adult attention-deficit/hyperactivity disorder: a machine learning analysis

Attention-deficit/hyperactivity disorder (ADHD) affects 5% of children world-wide. Of these, two-thirds continue to have impairing symptoms of ADHD into adulthood. Although a large literature implicates structural brain differences of the disorder, it is not clear if adults with ADHD have similar neuroanatomical differences as those seen in children with recent reports from the large ENIGMA-ADHD consortium finding structural differences for children but not for adults. This paper uses deep learning neural network classification models to determine if there are neuroanatomical changes in the brains of children with ADHD that are also observed for adult ADHD, and vice versa. We found that structural MRI data can significantly separate ADHD from control participants for both children and adults. Consistent with the prior reports from ENIGMA-ADHD, prediction performance and effect sizes were better for the child than the adult samples. The model trained on adult samples significantly predicted ADHD in the child sample, suggesting that our model learned anatomical features that are common to ADHD in childhood and adulthood. These results support the continuity of ADHD’s brain differences from childhood to adulthood. In addition, our work demonstrates a novel use of neural network classification models to test hypotheses about developmental continuity.publishedVersio

Evidence for similar structural brain anomalies in youth and adult attention-deficit/hyperactivity disorder: a machine learning analysis

Attention-deficit/hyperactivity disorder (ADHD) affects 5% of children world-wide. Of these, two-thirds continue to have impairing symptoms of ADHD into adulthood. Although a large literature implicates structural brain differences of the disorder, it is not clear if adults with ADHD have similar neuroanatomical differences as those seen in children with recent reports from the large ENIGMA-ADHD consortium finding structural differences for children but not for adults. This paper uses deep learning neural network classification models to determine if there are neuroanatomical changes in the brains of children with ADHD that are also observed for adult ADHD, and vice versa. We found that structural MRI data can significantly separate ADHD from control participants for both children and adults. Consistent with the prior reports from ENIGMA-ADHD, prediction performance and effect sizes were better for the child than the adult samples. The model trained on adult samples significantly predicted ADHD in the child sample, suggesting that our model learned anatomical features that are common to ADHD in childhood and adulthood. These results support the continuity of ADHD’s brain differences from childhood to adulthood. In addition, our work demonstrates a novel use of neural network classification models to test hypotheses about developmental continuity

Evidence for similar structural brain anomalies in youth and adult attention-deficit/hyperactivity disorder: a machine learning analysis

Attention-deficit/hyperactivity disorder (ADHD) affects 5% of children world-wide. Of these, two-thirds continue to have impairing symptoms of ADHD into adulthood. Although a large literature implicates structural brain differences of the disorder, it is not clear if adults with ADHD have similar neuroanatomical differences as those seen in children with recent reports from the large ENIGMA-ADHD consortium finding structural differences for children but not for adults. This paper uses deep learning neural network classification models to determine if there are neuroanatomical changes in the brains of children with ADHD that are also observed for adult ADHD, and vice versa. We found that structural MRI data can significantly separate ADHD from control participants for both children and adults. Consistent with the prior reports from ENIGMA-ADHD, prediction performance and effect sizes were better for the child than the adult samples. The model trained on adult samples significantly predicted ADHD in the child sample, suggesting that our model learned anatomical features that are common to ADHD in childhood and adulthood. These results support the continuity of ADHD’s brain differences from childhood to adulthood. In addition, our work demonstrates a novel use of neural network classification models to test hypotheses about developmental continuity

Characterizing neuroanatomic heterogeneity in people with and without ADHD based on subcortical brain volumes

Background Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder. Neuroanatomic heterogeneity limits our understanding of ADHD’s etiology. This study aimed to parse heterogeneity of ADHD and to determine whether patient subgroups could be discerned based on subcortical brain volumes. Methods Using the large ENIGMA-ADHD Working Group dataset, four subsamples of 993 boys with and without ADHD and to subsamples of 653 adult men, 400 girls, and 447 women were included in analyses. We applied exploratory factor analysis (EFA) to seven subcortical volumes in order to constrain the complexity of the input variables and ensure more stable clustering results. Factor scores derived from the EFA were used to build networks. A community detection (CD) algorithm clustered participants into subgroups based on the networks. Results Exploratory factor analysis revealed three factors (basal ganglia, limbic system, and thalamus) in boys and men with and without ADHD. Factor structures for girls and women differed from those in males. Given sample size considerations, we concentrated subsequent analyses on males. Male participants could be separated into four communities, of which one was absent in healthy men. Significant case–control differences of subcortical volumes were observed within communities in boys, often with stronger effect sizes compared to the entire sample. As in the entire sample, none were observed in men. Affected men in two of the communities presented comorbidities more frequently than those in other communities. There were no significant differences in ADHD symptom severity, IQ, and medication use between communities in either boys or men. Conclusions Our results indicate that neuroanatomic heterogeneity in subcortical volumes exists, irrespective of ADHD diagnosis. Effect sizes of case–control differences appear more pronounced at least in some of the subgroups